should check out Acquired growth hormone deficiency and hypogonadotropic hypogonadism in a subject with repeated head trauma, or Tintin goes to the neurologist:

We describe the unique case of a public figure who is well known for having delayed pubertal development and statural growth (Fig. 1). We believe we have discovered why Tintin, the young reporter whose stories were published between 1929 and 1975, never grew taller and never needed to shave....

Thanks to my friend Josh Bornstein for the pointer.